NIST Facilities for Calibrating Intravascular Brachytherapy Sources
C. G. Soares, M. G. Mitch, B. M. Coursey, S. M. Seltzer
Small photon- and beta-particle sources are being used in the treatment of heart disease to prevent reclosing of arteries after angioplasty. The challenges to the radiation physicist standardizing the dosimetry of these sources are the very close distances to the very small sources at which dosimetry is required, and the large number of isotopes and source geometries now under active investigation. Research at NIST focuses on dosimetry methods to meet these challenges including the use of precision-motion automated dosimetry measurement systems with miniature detectors, the development of primary standards for absorbed dose, and develop of methods to transfer source calibrations to users. The measurement systems available for these measurements at NIST include extrapolation ionization chambers with a variety of collection electrode areas, high-resolution radiochromatic film densitometry systems, micro-scintillators, well ionization chamber calibrators, thermoluminescent dosimeters, and a photo-stimulated luminescence imager. Work with these measurement systems will be discussed and measurement results presented.
This abstract was presented at the 33rd Annual Midyear Meeting, "Instrumentation, Measurements, and Electronic Dosimetry", Abstracts Session, 1/30/2000 - 2/2/2000, held in Virginia Beach, VA.